JP3377084B2 - Active energy ray-curable resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an active energy curable resin composition which is cured by active energy rays such as ultraviolet rays and electron beams. Specifically, an active energy ray-curable resin composition excellent in curability and cured film properties, which comprises an unsaturated polyester and a vinyl ether reactive diluent and an N-vinylamide reactive diluent as reactive diluents Regarding The active energy ray-curable resin composition of the present invention can be applied to various applications such as paper, overcoat agents for various plastic films, printing inks, wood coatings and the like. In particular, the active energy ray-curable resin composition of the present invention is useful as a woodwork paint.

[0002]

2. Description of the Prior Art Unsaturated polyesters obtained by esterification of ethylenically unsaturated dibasic acids such as maleic anhydride and fumaric acid and glycols such as ethylene glycol and propylene glycol as main raw materials are known. In the field of active energy ray-curable resins, a composition diluted with a reactive diluent such as a styrene monomer is widely used for applications such as wood coatings.

However, in recent years, it has been pointed out that styrene monomer deteriorates the working environment due to its volatility, odor and toxicity, and that a resin composition containing many styrene monomers has a problem that the film after curing is hard and brittle. is there. Moreover,
The active energy ray-curable resin composition using a styrene monomer as a reactive diluent also has poor curability as compared with the active energy ray-curable resin composition using an acrylic reactive diluent. Under such circumstances, there is a demand for an active energy ray-curable resin composition which is obtained by using a reactive diluent in place of a styrene monomer in combination with an unsaturated polyester and is capable of achieving rapid curing.

Acrylic reactive diluents are considered as reactive diluents to replace the styrene monomer. However, since the ethylenically unsaturated bond in the unsaturated polyester and the acryloyl group are generally poor in reactivity, an acrylic reactive diluent cannot provide sufficient cured film physical properties. As other reactive diluents, vinyl ether-based reactive diluents have been investigated. However, under the present circumstances, when diluted with a vinyl ether-based reactive diluent, cured film properties, particularly toughness, cannot be sufficiently obtained. Further, as the reactive diluent, an N-vinylamide-based reactive diluent has been investigated. Although the resin composition diluted with the N-vinylamide-based reactive diluent can provide a tough cured film, it cannot satisfy the physical properties of the cured film regarding alkali resistance.

[0005]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is an active energy ray curing based on an unsaturated polyester, which has good curability, a tough cured film, and excellent alkali resistance. An object is to provide a resin composition.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has found that a vinyl ether reactive diluent and an N-vinylamide reactive diluent are used as a reactive diluent in combination with an unsaturated polyester. It was found that the above object can be achieved when a reactive diluent is combined in a specific blending ratio, and the present invention has been completed.

That is, in the present invention, 30 to 90% by weight of an unsaturated polyester having an acid value of 1 or less, 5 to 30% by weight of a vinyl ether reactive diluent, 5 to 40% by weight of an N-vinylamide reactive diluent, And other reactive diluents 0
-30 weight% is contained, It relates to the active energy ray curable resin composition characterized by the above-mentioned.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The unsaturated polyester of the present invention is
It is obtained by subjecting an ethylenically unsaturated dicarboxylic acid and a polyhydric alcohol to an esterification reaction. Further, the unsaturated polyester of the present invention may be a combination of dicarboxylic acid other than ethylenically unsaturated dicarboxylic acid, monocarboxylic acid or monoalcohol, if necessary.

Examples of the ethylenically unsaturated dicarboxylic acid include maleic acid, maleic anhydride, fumaric acid, itaconic acid and acid anhydrides thereof.

As the polyhydric alcohol, diethylene glycol, ethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, 1,6-hexanediol, 1,4-
Examples thereof include cyclohexanediol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, glycerin, trimethylolpropane and pentaerythritol.

Examples of dicarboxylic acids other than ethylenically unsaturated dicarboxylic acid which may be optionally used in combination are adipic acid, sebacic acid, succinic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid and tetrachloro. Examples thereof include phthalic acid, chlorendic anhydride, glutaric acid, malonic acid, pimelic acid, and 2,2-dimethylsuccinic acid. Examples of monocarboxylic acids include propionic acid, 2-ethylhexylic acid, isobutyric acid and stearic acid, and examples of monoalcohols include n-butyl alcohol, 2-ethylhexyl alcohol and n-
Examples thereof include amyl alcohol, lauryl alcohol, stearyl alcohol, cyclohexanol, diethylene glycol monobutyl ether and the like.

The unsaturated polyester is produced by subjecting an ethylenically unsaturated dicarboxylic acid and a polyhydric alcohol, and if necessary, a dicarboxylic acid other than the ethylenically unsaturated dicarboxylic acid to an esterification reaction by a conventional method. Reaction temperature is 150
Is about 250 ° C., and the total reaction time is about 4 to 12 hours. Water generated during the esterification reaction is removed by a partial condenser. In the above esterification reaction, a solvent such as toluene may be used to accelerate the reaction.

The molecular weight of the unsaturated polyester of the present invention thus obtained can be varied over a wide range, but when a reactive diluent is used in combination, good actinic radiation curability,
To obtain the physical properties of the cured film, the weight average molecular weight (polystyrene-equivalent weight average molecular weight measured by GPC, the same applies hereinafter) is about 500 to 30,000, preferably 500 to 20.
The range of 000 is preferable. Weight average molecular weight is 50
When it is less than 0, the curing rate tends to be low and the cured film tends to be brittle, and when it is more than 30,000, the viscosity is high and handling is difficult.

The unsaturated degree of the unsaturated polyester of the present invention (the number of moles of ethylenically unsaturated group contained in 1 g) is
The optimum conditions vary depending on the required physical properties and the ratio of the reactive diluents to be used, but 0.5 × 10 ⁻³ to 10 × 10 ⁻³ mol /
About g is preferable. Unsaturation is 0.5 × 10 ^-3 mol / g
If it is smaller, it is difficult to obtain sufficient curability, and it is 10
If it is more than × 10 ^-3 mol / g, resin design becomes difficult.

The unsaturated polyester of the present invention has an acid value of 1 or less from the viewpoint of long-term storage stability of a resin composition containing a vinyl ether reactive diluent and an N-vinylamide reactive diluent. It was made to react like this.
In order to easily adjust the acid value to 1 or less, it is preferable to use the ethylenically unsaturated dicarboxylic acid and the dicarboxylic acid other than the ethylenically unsaturated dicarboxylic acid so that the carboxyl group equivalent is smaller than the hydroxyl group equivalent of the polyhydric alcohol. preferable.

The unsaturated polyester of the present invention can also be used by reacting the residual hydroxyl group with a polyisocyanate compound. The polyisocyanate compound is
By being present together with the unsaturated polyester in the active energy ray-curable resin composition, it can be used as a so-called two-pack type, and by reacting in advance with the residual hydroxyl groups of the unsaturated polyester, the isocyanate-modified unsaturated polyester It can be used as part.

Examples of the polyisocyanate compound include isophorone diisocyanate, 2,4-tolylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane diisocyanate, 1,6-hexane diisocyanate, lysine diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate. Isocyanates and multimers thereof are included. The proportion of the polyisocyanate compound used is such that the isocyanate group of the polyisocyanate compound is 0.8 equivalent or less with respect to 1 equivalent of the residual hydroxyl group of the unsaturated polyester.
The unsaturated degree and the weight average molecular weight of the isocyanate-modified unsaturated polyester are preferably within the above ranges.

The vinyl ether reactive diluent of the present invention has CH ₂ ═CH—O— or CH ₂ ═C (CH ₃ ) in the molecule.
1 to 10 functional groups represented by —O—, preferably 1 to
It is a compound having two. Specific examples of the vinyl ether-based reactive diluent include, for example, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether,
Amyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, ethylene glycol butyl vinyl ether, triethylene glycol methyl vinyl ether, propenyl ether propylene carbonate, aminopropyl vinyl ether, 2-diethylaminoethyl vinyl ether, cyclohexanedimethanol monovinyl ether, hydroxy Ethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, ethylene glycol divinyl ether, polyethylene glycol divinyl ether, Propylene divinyl ether, polytetramethylene glycol divinyl ether, trimethylolpropane trivinyl ether, pentaerythritol tetra vinyl ether. These vinyl ether compounds may be used alone or in combination of two or more. Among the vinyl ether-based monomers, those having a hydroxyl group can be used by reacting with a polyisocyanate compound. Examples of the polyisocyanate compound include those exemplified above.

The vinylamide-based reactive diluent of the present invention is

[0020]

[Chemical 1]

It is a compound having a functional group represented by:
Specific examples of the vinylamide-based reactive diluent include N-vinylformamide, N-vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam and the like. As these N-vinylamide compounds, N-vinylformamide is preferable. These N-vinylamide compounds may be used alone or in combination of two or more.

The active energy curable resin composition of the present invention contains 30 to 90% by weight of the unsaturated polyester, 5 to 30% by weight of the vinyl ether reactive diluent and N-.
It contains 5 to 40% by weight of a vinylamide-based reactive diluent. 5% by weight of vinyl ether reactive diluent
If it is less than 30% by weight, the alkali resistance is insufficient.
If it is more, the curability and the physical properties of the cured film will be insufficient. If the amount of the N-vinylamide reactive diluent is less than 5% by weight, the curability and the physical properties of the cured film will be insufficient, and if it is more than 40% by weight, the alkali resistance will be deteriorated. From these points, the vinyl ether-based monomer is preferably 10% by weight or more, and 2
It is preferably 5% by weight or less. Further, the N-vinylamide reactive diluent is preferably 10% by weight or more and 30% by weight or less.

Further, the active energy curable resin composition of the present invention requires a monofunctional or difunctional or higher functional reactive diluent other than the vinyl ether type reactive diluent and the N-vinylamide type reactive diluent. Depending on 0 to 0 of the resin composition
You may mix | blend 30 weight%. Specific examples of the reactive diluent other than the vinyl ether-based reactive diluent and the N-vinylamide-based reactive diluent include, for example, tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6. -Hexanedi (meth) acrylate, bisphenol A poly (repeating number about 1 to 4) ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane mono or poly (repeating units 1 to 3) ethoxy Examples thereof include triacrylate, pentaerythritol poly (meth) acrylate, dipentaerythritol poly (meth) acrylate, acryloylmorpholine, phenoxyethyl acrylate and nonylphenoxyethyl acrylate.

Further, the active energy ray-curable resin composition of the present invention is not necessary when the resin composition is cured by an electron beam or the like as an active energy ray, but when it is cured by ultraviolet rays, it is a resin. Usually, 1 to 15 parts by weight of a photopolymerization initiator can be contained per 100 parts by weight of the composition. As the photopolymerization initiator, Darocur 1173, Irgacure 651, Irgacure 1
Various known materials such as 84, Irgacure 907 (manufactured by Ciba-Geigy), benzophenone and the like can be used. Also, if necessary, various additives other than the above, for example,
Examples include polymerization inhibitors, antioxidants, ultraviolet absorbers, light stabilizers, solvents, defoamers, and leveling agents. Depending on the case, a pigment, a silicon compound or the like may be contained according to the purpose without departing from the purpose of the present invention.

[0025]

The active energy ray-curable resin composition of the present invention has good curability, a tough cured film, and excellent alkali resistance. Further, the active energy ray-curable resin composition of the present invention has a relatively low viscosity and is easy to handle.

[0026]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. In the following, "parts" and "%" are based on weight unless otherwise specified.

Synthesis Example 1 (Production of Unsaturated Polyester A) A flask equipped with a stirrer, a thermometer, a nitrogen blowing tube, a partial condenser, and a reflux condenser was charged with 54 parts of maleic anhydride and 179 parts of adipic acid, 1,6. -152 parts of hexanediol, 115 parts of neopentyl glycol, and 25 parts of toluene were charged. Then, nitrogen gas was blown into the system to raise the temperature to 170 ° C. and keep the temperature for 1.5 hours, further raise the temperature to 220 ° C. over 2 hours, and then keep the temperature for 3 hours to give an acid value of 0.64 mgKOH /
It became g. The amount of dehydration during this period was 59 parts. After increasing the nitrogen flow rate and removing toluene, water, etc. for 30 minutes,
Cooled and removed. The resulting unsaturated polyester is referred to as unsaturated polyester A. The acid value of the unsaturated polyester A was 0.5 mgKOH / g, and the weight average molecular weight by GPC was 5,400.

Synthetic Example 2 (Production of Unsaturated Polyester B) In Synthetic Example 1, 54 parts of maleic anhydride, 201 parts of adipic acid, 130 parts of 1,6-hexanediol, 115 parts of neopentyl glycol and 25 parts of toluene were changed. The reaction was performed in the same manner as in Synthesis Example 1 except that the reaction was carried out, and the temperature was kept at 220 ° C. for 7 hours to give an acid value of 1 mgKOH / g. The amount of dehydration during this period was 62 parts. It was taken out in the same manner as in Synthesis Example 1. The unsaturated polyester B thus obtained had an acid value of 0.95 mgKOH / g and a weight average molecular weight of 9100 as measured by GPC.

Example 1 60 parts of unsaturated polyester A, 20 parts of N-vinyl formamide, 20 parts of hydroxybutyl vinyl ether, 0.1 part of hydroquinone as a polymerization inhibitor and 3 parts of a photopolymerization initiator (Irgacure 184, manufactured by Ciba Geigy). Was added, mixed and dissolved to prepare a varnish having a viscosity of 240 cps (25 ° C.).

Examples 2 to 4 and Comparative Examples 1 to 4 Table 1 shows the type or amount of unsaturated polyester or the type or amount of reactive diluent used in Example 1.
A varnish was prepared in the same manner as in Example 1 except that the varnish was changed as shown in FIG.

The varnishes obtained in Examples and Comparative Examples were evaluated as follows. The results are shown in Table 1.

(1) Curing test varnish was applied on a glass plate with an applicator of 200 μm, high pressure mercury lamp 80 W / cm (1 lamp), irradiation distance 1
The curability was measured by changing the irradiation dose under the condition of 0 cm.

(2) Elongation and strength The elongation and strength were measured using the cured film obtained in the curability test (irradiation dose of 310 mJ / cm ² ). Test piece: width 6 mm, length 5 cm (distance between chucks 2.5
cm) Elongation: It was pulled at a pulling speed of 50 mm / min, and the elongation rate against its own length at break was measured. Strength: Tensile speed was pulled at 50 mm / min, and stress at break was measured.

(4) Acid resistance, alkali resistance Curing test (2% hydrochloric acid aqueous solution, 2% sodium hydroxide aqueous solution) was dropped on the surface of the cured film obtained by the curing resistance test (irradiation dose 310 mJ / cm ² ), and the lid was closed. Then, the appearance change after standing for 1 hour was examined. ○: No change. △: Lifted. × ... Tear or swell.

[0035]

[Table 1]

In Table 1, NVF: N-vinylformamide, HBVE: hydroxybutyl vinyl ether, DV
E-3: Indicates triethylene glycol divinyl ether. <Note> indicates below the measurement limit.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI C08F 226: 02) (56) References JP-A-7-24411 (JP, A) JP-A-7-69686 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08F 283/01 C08F 290/00-290/14 C08F 299/00-299/08 C09D 5/00

Claims (3)

(57) [Claims] 1. An unsaturated polyester 30 having an acid value of 1 or less.
~ 90% by weight, vinyl ether reactive diluent 5-30
An active energy ray-curable resin composition, characterized in that the active energy ray-curable resin composition contains 5% by weight, an N-vinylamide reactive diluent of 5 to 40% by weight, and another reactive diluent of 0 to 30% by weight. 2. An N-vinylamide reactive diluent is N-
The active energy ray-curable resin composition according to claim 1, which is vinylformamide. 3. The active energy ray-curable resin composition according to claim 1, further comprising a photopolymerization initiator and / or an additive.